The Sigma 18-50mm F2.8 DC DN Contemporary ($599) should appeal to photographers using APS-C sensor cameras. It's the slimmest, lightest F2.8 zoom, while its bright, close-focusing optics offer real benefits for photographers looking to start off with just a kit lens. It's available for Canon, Fujifilm, L-mount, and Sony camera systems, costs much less than first-party alternatives such as the Editors' Choice-winning Sony E 16-55mm F2.8 G ($1,399.99), and is easier to carry around than our affordable Editors' Choice winner, the $800 Tamron 17-70mm F2.8 Di III-A VC RXD.

Editors' Note: This review was originally published on October 19, 2021. It has been updated to reflect changes in price and availability for additional camera systems.

Design: An F2.8 for Smaller Cameras

The 18-50mm lives up to its small-and-light billing. It measures 2.9 by 2.6 inches (HD) and weighs just 10.2 ounces. It's lighter and smaller than its closest competitor, the Tamron 17-70mm F2.8 (4.7 by 2.9 inches and 1.2 pounds), but sacrifices some coverage on both ends of the focal range to get there.

(Credit: Jim Fisher)

Sigma sells the lens in four versions, so you can get it for Canon RF, Fujifilm X, L-mount Alliance, and Sony cameras. Only a handful of L-mount cameras with APS-C sensors exist—the Leica CL and TL2 are the most recent. Canon owners should pay special attention as there aren't any first-party F2.8 lenses made for APS-C cameras like the EOS R10. All of Fujifilm's X series cameras and lenses are APS-C, but the Sigma stands tall as a value option that's half the price of the $1,200 XF 16-55mm F2.8 R LM WR II. I reviewed the Sony version of the lens.

(Credit Jim Fisher)

The lens optics cover the APS-C sensor of entry-level models like the Sony a6100 and midrange options like the Leica CL. I didn't have ready access to an APS-C camera for this review, so I paired the lens with the full-frame Sony a7R IV. In that camera's APS-C mode, it produces 26MP images.

Construction: Sturdy, But Not All-Weather

The 18-50mm's barrel is made from thermally stabilized composite—fancy words for high-quality plastics—with dust and splash protection at the mount only. The front element supports 55mm threaded filters and Sigma includes a petal-style lens hood that offers extra protection from smudges and flare. The glass isn't protected with oil-repellent fluorine, so you need to take a little extra care when cleaning it.

(Credit: Jim Fisher)

The 18-50mm is smallest at the 18mm setting. Its inner barrel telescopes out to zoom in to tighter focal lengths, extending by about an inch. The zoom ring turns with a pleasing amount of resistance and stays in place once set. Like other zooms, the Sigma's barrel has rubber ridges that help with grip, for example, when you're wearing gloves in cold weather.

Autofocus: Snappy Response, Useful Macro

The 18-55mm's autofocus performance is top-notch. The STM motor drives focus quickly and quietly, racking from close to far in an instant. Manual focus is also an option, but I'm less happy with the experience. The focus control ring is narrow and close enough to the lens mount to be a little uncomfortable to turn. Aside from that gripe, it works as expected, with a nonlinear response and a very long throw—good for making precise adjustments.

(Credit: Jim Fisher)

The nonlinear manual focus may turn off cinematographers—it makes it replicate focus racks from take to take—but it's a very good choice for vloggers and more casual video shooters. Autofocus is quiet enough to stay off the soundtrack, and focus breathing is practically absent.

The only thing missing is optical stabilization. The 18-50mm's size makes it a good fit for use with gimbals if you're serious enough about handheld video to use one. It's an especially good accessory to consider if you're using the Sony ZV-E10 for handheld work—its digital stabilization is effective but tightens the view of the attached lens.

(Credit: Jim Fisher)

The lens can focus very close; its macro capability works best at 18mm where it focuses as close as 4.8 inches for 1:2.8 magnification. The focus distance is measured from the sensor, not the front of the lens—the nearest working distance is only about an inch from the front element. Therefore, you should take off the lens hood for macros and take extra care not to position the camera where it casts a shadow over your subject.

(Credit: Jim Fisher)

The 18-55mm's depth of field is quite slim when focusing close, even with the aperture stopped down. If you're photographing a perfectly flat subject, you'll note some field curvature at close distances—if the center is sharply focused, edges will be a bit blurred, and vice versa. The curvature is gone at 50mm, and the lens can still focus as close as 11.9 inches at that focal length.

Image Quality: 18-50mm Contemporary in the Lab

I paired the 18-50mm with the Sony a7R IV in its 26MP APS-C mode for testing in the lab and in the field; I used Imatest software to check its resolution. It turns in strong performance across its zoom range, delivering resolution in the very good range (2,600 lines) at f/2.8 and netting outstanding results when stopped down to f/5.6 and f/8 (3,100 lines).

(Credit: Jim Fisher)

In-camera corrections remove distortion and compensate for darkened corners for JPG capture. Raw photographers will contend with visible barrel distortion at 18mm and a pincushion effect at the long end. We expect Adobe to add a one-click correction profile for Lightroom Classic soon. In the meantime, dial in about +25 distortion correction at 18mm, -8 at 35mm, and -10 at 50mm to straighten things out.

I'm quite pleased with the bokeh quality. Backgrounds fall off softly and defocused highlights look good, especially when zoomed in to portrait-friendly focal lengths, where they're mostly rounded at f/2.8. Narrowing the aperture to f/4 or f/5.6 rounds them into good-looking spheres, but the seven-blade aperture introduces a polygonal effect at f/8.

(Credit: Jim Fisher)

Landscape photographers can get decent, but not pinpoint, sunstars from the 18-50mm. Bright points of light take on a starburst effect, with distinct, but not sharply cut, points at f/16. You get a bit sharper lines at f/22, but it comes at the cost of resolution—digital photos are always a little soft at the smallest f-stops—and the lens is more prone to show ghosting. You can use this behavior for effect, though, like in the photo above.

Competitors Vary by System

The appeal and value of the 18-50mm F2.8 DC DN Contemporary vary depending on which camera system you own. I'll start with Sony, which is the longest-running mount for which the lens is available. The first E-mount cameras debuted in 2011. Because of this and Sony's decision to open its mount to third parties from the start, Sony owners have the largest number of standard zoom lenses to consider.

(Credit: Jim Fisher)

Sony's basic starter lens is the E 16-50mm F3.5-5.6 OSS (also available in a Mark II edition with identical optics). Neither version is a world beater, but as they've been bundled with Sony cameras for years there's a good chance it's the first lens you used with your camera. There are several upgrade options with F2.8 optics, including our Editors' Choice Tamron 17-70mm F2.8 Di III-A VC RXD, an $800 lens that's larger but comes with optical stabilization. Sony has a premium G series entry too, the E 16-55mm F2.8 G, it's an ideal standard zoom but its $1,400 price tag puts it out of reach of some budgets.

(Credit: Jim Fisher)

The story is very similar for Fujifilm. The Tamron 17-70mm is also available for Fuji X cameras. Fujifilm recently released an upgraded Mark II version of its older XF 16-55mm F2.8 R LM WR zoom at the same $1,200 price, but we've not had a chance to review it. The 16-55mm F2.8 II comes with upgraded optics and additional on-barrel controls, plus it has the full weather protection that's missing from the Sigma.

(Credit: Jim Fisher)

Sigma's compact zoom is a compelling option for the niche of L-mount photographers using a Leica CL or TL2—its size matches well and it's available for around a quarter of the price of the Vario-Elmar-T 18-56mm F3.5-5.6 ($1,995). Although that lens covers essentially the same angles of view, it doesn't blur away backgrounds to the same degree.

There are very few third-party options for Canon EOS R cameras. Canon added APS-C options to this line in 2022 (the EOS R10 and R7 were the first), but waited two years before allowing third parties to make autofocus lenses. Because of this, the Sigma only goes up against the basic RF-S 18-45mm F4.5-6.3 kit zoom or the upgraded RF-S 18-150mm F3.5-6.3, a pair of lenses with dimmer optical formulas. If you're an enthusiast or simply want the background blurring power and low light performance that comes with an F2.8 lens the Sigma is the best, and at this point only, option. It's unclear at this point if Tamron will release its 17-70mm with an RF-S mount for these cameras.

Verdict: A Reasonably Priced Step-Up Lens

The Sigma 18-50mm F2.8 DC DN Contemporary is one of the better value options for photographers who use an APS-C sensor camera and want a standard zoom lens with background-blurring power and optics that are far better than you get with bundled kit lenses. There's plenty to like about the Sigma, as it's optically excellent and provides fast and accurate autofocus. The 18-50mm can notably capture shots with a 1:2.8 macro reproduction, too, adding to its versatility. The lack of full weather sealing and a fluorine coating are among its biggest weaknesses.

Its place in the market varies based on system: Canon and L-mount owners simply don't have another F2.8 standard zoom that's made for APS-C sensors, while Sony and Fujifilm photogs will have to weigh the Sigma's light design and low price versus the larger, slightly pricier, but stabilized Tamron 17-70mm F2.8 Di III-A VC RXD. The Tamron wins out as Editors' Choice for the systems which it's available.